A US woman who shot and killed her husband and two adult children before taking her own life is thought to have committed the shocking crime as a result of being ostracised from the religion she was raised in.

Every time I tell a mate I’m doing a story on cryptocurrency, they invariably ask me the same two questions: should they invest their own hard-earned money, and which cryptocurrency will get them a Lamborghini/yacht/island quickest?

Inquiry into grandparents as guardians

Federal parliament will hold an inquiry into problems faced by grandparents who are left to raise their grandchildren.

West Australian Liberal Senator Dean Smith said the number of grandparents who have postponed retirement to look after children was on the rise, yet the government knew little about the challenges they faced.

"Some of the stories these grandparents have shared are inspiring and heartrending in equal measure," Senator Smith said in a statement on Monday.

"At a time when many of their friends are making retirement plans, these heroic grandparents are dealing with the many physical, emotional and financial challenges that come with raising young children."

The Senate has referred the inquiry to its Community Affairs References Committee.

Senator Smith said the inquiry would look at what support could be offered to grandparents who are raising their grandchildren.